A continuing problem in the packaging of beverage containers such as cans and bottles is to separate the containers into groups while the containers are moving through a packaging machine at very high speeds, and to load the groups into cartons which are also moving at very high speeds through the machine. The high speeds at which packaging machines are run require the containers to be moved and segregated in such a way as to minimize the danger of the containers falling and jamming the machine. The movement of the groups of containers into the rapidly moving cartons must also be carried out smoothly to avoid misalignment, which could also result in a jam.
The cartons in which beverage containers are packaged are commonly fed into the packaging machine in the form of generally flat folded blanks which are opened to create a carton in an intermediate stage of fabrication having open ends and leading and trailing upright panels. Various means for feeding and segregating the beverage containers into groups of the desired number have been employed. For example, endless chains carrying lugs for contacting and pushing the containers into partially folded blanks have been employed. Such arrangements require exact timing between the lug chains and both the principal container moving means and the carton moving means, and are not desirable for use in modern high speed packaging machines.
In another arrangement described in U.S. Pat. No. 3,778,959 to Langen et al, open-ended carton sleeves are moved downstream while rows of containers are fed to an adjacent conveyor. Container separating means in the form of rakes or arms are carried by the adjacent conveyor and extend across the width of the conveyor so as to separate the containers into groups. The groups are maintained in their segregated condition by the arms as the adjacent conveyor moves the groups of containers parallel to the carton sleeve moving means. Guide rails at a downstream location assist in moving the groups into the carton sleeves. Although an improvement over other slower more complicated machines, this machine requires a number of container conveyors working in concert to move the containers from the infeed conveyor to the carton sleeves. It also requires the separating arms to extend across the entire width of the adjacent conveyor in order to segregate the containers at an upstream point relatively distant from the location where the containers enter the carton sleeve. This in turn requires the separating arms to be structurally able to extend in cantilever fashion across the full width of the conveyor to which it is attached, resulting in a considerably more massive structural arrangement than desired, both with respect to the arms themselves, the conveyor carrying them, and the support structure connecting the arms and the conveyor. This in turn takes up more space within the confines of the packaging machine than desired.
Another approach to the problem is described in U.S. Pat. No. 4,237,673 to Calvert et al., which discloses a packaging machine in which carton blank sleeves are pushed over a support surface by flight bars. The flight bars extend beyond the ends of the carton sleeves across the remaining width of the support surface, and function as metering bars to separate the beverage containers into groups of predetermined number and to push the containers along the guides leading to the open ends of the carton sleeves. The containers must thus cross a dead plate in order to enter the carton, encountering friction forces which oppose a smooth passage into the carton. The metering bars, like the arms of Langen et al., are long and heavy, requiring strong support means and a relatively large amount of space in which the metering bars and their support structure can move. Further, by relying on line pressure and the movement of the metering bars to move the containers from the infeed conveyor to the carton sleeves, it is necessary to provide dampers to take up the container feed pressure. In addition, the use of combination flight bars and metering bars makes it a relatively time consuming process to change to a different carton size.
It would be desirable to employ a container feed which is not dependent upon the container line pressure to move containers downstream and which does not require an elongated bulky metering bar or arm to separate the containers into groups of predetermined number.